The present invention is a development of a fuel injection system of the type generally revealed in the Stumpp et al. U.S. Pat. No. 4,018,200, which is assigned to the same assignee. A fuel injection system which only permits limited enrichment rates already exists.
The advantage of the fuel injection system according to the invention which comprises the characterizing features that very high enrichment rates for influencing the fuel-air mixture as a function of the operating parameters of the internal combustion engine can be produced in the control pressure line by simultaneously reducing the differential pressure at the fuel metering valve and the pressure produced by the resetting force on the air metering member.
Advantageous developments and improvements can be made to the fuel injection system defined by the measures described herein.
A particularly advantageous measure consists in arranging the first throttle in the region of the connection point between the control pressure line and the fuel supply line and in arranging the regulating valves, the second throttle, the pressure chamber and the sequentially controllable electromagnetic valve downstream of the first throttle. As a result of this measure, it is possible to obtain higher enrichment rates in the fuel injection system without increasing the pressure.
The invention will be better understood and further objects and advantages thereof will become more apparent from the ensuing detailed description of preferred embodiments taken in conjunction with the drawings.